The object of the present invention is a proof body for a measuring sensor designed for a weighing apparatus and, more particularly, for bathroom scales, as well as a weighing apparatus provided with such proof bodies. For such an application, it is important that a sensor be available, which is reliable and inexpensive.
Generally, these weighing apparatuses include measuring sensors comprising a proof body shaped as a deformable parallelogram carrying strain gauges in its hinge regions. This implies that the strain gauges be capable of resisting both to a traction and to a compression and necessitates the use of strain gauges which are expensive.
Quite inexpensive strain gauges are available which can be mass-produced and which consist of a thin glass substrate on which are formed by deposition metallised areas forming resistors, of which the resistance varies as a function of the deformation of the substrate The drawback of these strain gauges lies in the fact that they offer a resistance to deformation by traction which is poor.
One of the purposes of the present invention is to provide a proof body for weighing apparatuses in which the strain gauges are subjected only to compression deformations and strains, so that inexpensive strain gauges, such as those described above or any other type of gauge may be used without affecting adversely the reliability and the useful life of the weighing apparatus.
The object of the present invention is a proof body for a weighing apparatus and a weighing apparatus, in particular bathroom scales, equipped with such proof bodies, which are characterised by the features set forth in claims 1 and 3.